The first purely decorative features which we may imagine to have been introduced,--if the logical scheme I have been supposing had been strictly followed out,--would be the base-course of a wall, the impost to sever the pier from the arch, and the drip, or label, to draw the line between the arch and the wall. These mouldings in their elementary forms are alike. In Anglo-Saxon they were usually square courses (Fig. 237); in Norman, their simple form is the same with the angle cut off (Fig. 238). [Illustration: Fig. 237.] [Illustration: Fig. 238.] This form for the impost and the label was adopted also, very usually, for string-courses; but, in all positions, it was soon relieved by additional forms, as the double chamfer, the quirk, the quirk and hollow, and the round and hollow, or the cyma (Fig. 239). [Illustration: Fig. 239.] The primary idea of a capital to a decorative shaft is that of a cubical block over which the impost returns. It is, in fact, the upper course of the square portion of the pier for which the shaft has been substituted, or out of the substance of which it is cut (Fig. 240). The object, therefore, to be kept in view in designing the capital, is to devise the best method or methods of bringing about a transition from the cylindrical shaft to the square impost or abacus. The simplest form used in early Norman work is little more than the mathematical solution of the problem, which would be the frustum of an inverted cone intersected by the faces of the cube. [Illustration: Fig. 240.]